Sign language: A Lebanese woman protests outside the Arab League headquarters in Beirut

With US Secretary of State Condoleezza Rice due to arrive for talks with the Israeli and Palestinian leaders, a US state department official said: "We're encouraging Israel to exercise caution to avoid the loss of innocent life."

The European Union criticised what it called Israel's ''disproportionate use of force'' and also demanded an immediate end to Palestinian militant rocket attacks on Israel.

Prime Minister Recep Tayyip Erdogan of Turkey, one of Israel's few Muslim allies, said there was "no humane or legal justification for the attacks on Gaza''.

Mr Abbas's spokesman, Nabil Abu Rudeina, blamed Israel for the suspension of talks on all levels.

"In light of the Israeli aggression such communication has no meaning," he said.

A spokesman for Israel's Foreign Minister Tzipi Livni, Arye Mekel, said the Palestinian decision was a mistake and expressed hope negotiations would resume.

Mr Abbas restarted the talks after a conference in November in the US city of Annapolis.